Differential relationships between sub‐traits of BIS-11 impulsivity and executive processes: An ERP study Julia W.Y. Kam, Rachelle Dominelli, Scott R. Carlson ⁎ Department of Psychology, University of British Columbia, 2136 West Mall, Vancouver, British Columbia, Canada V6T 1Z4 abstract article info Article history: Received 19 October 2011 Received in revised form 5 May 2012 Accepted 24 May 2012 Available online 29 May 2012 Keywords: Impulsivity AX-CPT Inhibition P3 amplitude N2 amplitude There is mixed evidence for a relationship between impulsivity and executive functions. Although impulsiv- ity is heterogeneous, previous research did not examine partial relationships controlling for shared variance across sub-traits to evaluate the specificity of these associations. Eighty-five undergraduates completed the Barratt Impulsiveness Scale-11 (BIS-11) and the AX-expectancy version of the Continuous Performance Task (AX-CPT). This task engenders a conflict between two response tendencies by manipulating the fre- quency of specific trial types. We conducted mixed model analyses to determine the unique variance in be- havioral and electrophysiological indices of relevant cognitive functions accounted for by the facets of BIS-11. Motor Impulsiveness was associated with smaller P3 across sites and conditions suggesting a general cogni- tive limitation not specific to the condition requiring the most inhibition, and larger N2 in some conditions indicating heightened conflict detection. Non-Planning Impulsiveness was related to smaller N2 when inhibiting a primed response and with greater P3 in some contexts. Attentional Impulsiveness appeared to be associated with an inefficient conflict detection system indicated by relatively normal engagement in trials involving the non-potent response, but relatively over engagement in the prepotent condition. Our findings suggest that sub‐traits of impulsivity are differentially related to executive processes. © 2012 Elsevier B.V. All rights reserved. 1. Introduction Self-regulation is fundamental to trait conceptualizations of im- pulsivity. Relative problems with higher order functions influencing capacity for self-control, such as “top-down” attention (e.g., Posner and Rothbart, 2007) and prefrontally-mediated inhibitory processes (e.g., Miller and Cohen, 2001; Shimamura, 2000), may serve as neuro- psychological contributors to impulsivity as a personality dimension. Nevertheless, despite some studies reporting associations between impulsive traits and behavior-based measures of these so-called ex- ecutive functions (Keilp et al., 2005; Pietrzak et al., 2008), others have found no such relationship (Horn et al., 2003; Reynolds et al., 2006). These mixed findings may stem from the multi-faceted nature of impulsivity, an issue that has not received much attention in re- search on cognition and personality until recently. Although several measures of trait impulsivity exist, arguably the one with the longest track record that is still in wide use is the Barratt Impulsiveness Scale (BIS; Stanford et al., 2009). The most recent ver- sion, the BIS-11, measures three related but dissociable sub- dimensions of impulsivity. While some studies have examined zero- order correlations between BIS-11 facets and executive function mea- sures (Enticott et al., 2006; Gorlyn et al., 2005; Keilp et al., 2005; Pietrzak et al., 2008; Spinella, 2004; Swann et al., 2002), to our knowl- edge no work has examined whether these facets have unique rela- tionships with measures tapping executive functions. The BIS-11 subscales have specific correlates with clinically important under- controlled behaviors such as binge drinking (Carlson et al., 2010) and manic symptoms (Swann et al., 2008). As such, the relationships between unique variance in one facet and measures of executive function may provide clues to the cognitive processes underlying per- sonality risk for disinhibited behaviors. Further, most studies examining BIS-11 subscales have used behavior-based measures of executive functions (see Harmon-Jones et al., 1997; Goya-Maldonado et al., 2010 for exceptions). Some indi- viduals with high trait impulsivity may compensate for their cogni- tive limitations by engaging other resources with little observable difference in behavior. Therefore, behavioral responses may be less sensitive indices of underlying executive limitations than are direct measures of neural activity (e.g., Goya-Maldonado et al., 2010). Event-Related Potentials (ERPs) are measures of neural activity that have been used in studies of executive functions (e.g., Fallgatter et al., 1997; Roberts et al., 1994; Bokura et al., 2001; Bruin and Wijers, 2002; Kirmizi-Alsan et al., 2006; Smith et al., 2008; Tekok- Kilic et al., 2001). Some ERP measures have been related to trait im- pulsivity in tasks that are influenced by a variety of demands, not all of which are necessarily directly related to executive functions (e.g., International Journal of Psychophysiology 85 (2012) 174–187 ⁎ Corresponding author at: Department of Psychology, University of Minnesota Du- luth, 320 Bohannon Hall, 1207 Ordean Court, Duluth, MN 55812–3010, USA. Tel.: +1 218 726 6428; fax: +1 218 726 7186. E-mail address: carls116@d.umn.edu (S.R. Carlson). 0167-8760/$ – see front matter © 2012 Elsevier B.V. All rights reserved. doi:10.1016/j.ijpsycho.2012.05.006 Contents lists available at SciVerse ScienceDirect International Journal of Psychophysiology journal homepage: www.elsevier.com/locate/ijpsycho